(a) Field of the Invention
The present invention relates to a chemical and heat-resistant styrene-based resin. More particularly, the present invention relates to a styrene-based resin composition that is resistant to chemicals including maleimide compounds, acrylate copolymers and oil elements, in addition to being resistant to heat, such that the resin composition can be used in a variety of automobile parts.
(b) Description of the Related Art
ABS (acrylonitrile-butadiene-styrene) and PC/ABS (polycarbonate/ABS) are most commonly used for interior parts of the automobile. However, when these materials come into direct contact with liquid-type aromatics, they weaken over time and become more prone to experience environmental stress cracks (ESCs). In addition, the application of substances often used in testing the chemical resistance of automobile parts such as brake oil, engine oil, gasoline, etc. discolor ABS and PC/ABS and crack areas on the materials where stress is concentrated. Accordingly, much research has gone into the development of a styrene-based composition used in vehicles that is resistant to ESCs and provides chemical resistance that is superior to that of ABS and PC/ABS.
In more detail, conventional chemical-resistant resin compositions are manufactured by increasing the content of acrylonitrile or the molecular weight of SAN (styrene-acrylonitrile) in ABS components. However, such adjustments rid or minimize some of the advantageous properties of the resin and complicate the manufacturing process. Accordingly, using such resin-based compositions in parts for vehicles becomes impractical, and even if these adjustments are implemented the chemical-resistance effects attained are minimal.
There is also a process in which a polyolefine-based resin is mixed with ABS to increase chemical resistance. A block Copolymer must be used with this composition to enable commercial use. However, in actual use, the polyolefine-based resin becomes separated in phase from the ABS, thereby greatly reducing the mechanical properties of the composition.